Zero foils for calculating machine



Oct. 21, 1958 J. L. MODY ZERO FoLs FOR CALCULATING MAHINE 5 Sheets-Sheet1 Filed may 31, 1955 Oct. 2l, 1958 J. L, MOODY ZERO FoILs FORCALCULATING MACHINE 5 Sheets-Sheet 2 Filed May 31, 1955 oct; 2 1, 195sJ. L MODY 2,857,096

ZERO FOILS FOR CALCULATING MACHINE I Filed May 31, 1955 5 Shets-Sheet 3'5 /52 E E. l 165 I, 52 L /7/ ,/72 il,| 3|. L!! El El l l l rH` E m '70:L/70 /lo HS/ i-l: I

| Il IlllA mmf Oct. 21, 1958 J. L. MooDY zERo Fons FOR CALCULATINGMACHINE 5 Sheets-Sheet 4 Filed Hay 31, 1955 oct. 21, 195s J. L. MOODY i2,857,096`

ZERO FOILS FOR CALCULATING MACHINE Filed May 31, 1955 5 Sheets-Sheet. 5

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nited tats Patented Oct. 2, .T1953 li i.

FILS EUR CALCULATING MACHINE .lohn L, Moody, akiand, Calif., assigner toFriden, Inc., a corporation of California Application May 31, 1955,Serial No. 512,100

6 Claims. (Cl. 23S- 1) l" his invention relates to check dials for acalculating machine such as the well known Friden Calculating lvlachine,and more particularly, to automatically operating Zero foiis, or covers,for such Check dials.

lt is among the objects of the invention to provide automaticallyoperating zero foils, or covers, for calculating machine check dials,such as are shown in Patent No. 2,279,455, granted April l4, 1942, to C.M. F. Friden el al., which foils or covers are selectively operated tocover and uncover the window openings, or apertures, in the machinecover through which the check dials are vie' d. in its preferred form,the zero foils are controilable by a decimal indicator manually movablefrom order to order of the check dials to uncover all of the windowopenings to the right of the decimal indicator while leaving thosewindow openings to the left of the decimal indicator closed. Preferably,also, these foils, or covers, are independently operable in each orderof the check dials to uncover the corresponding window openings if thecoordinal check dials are turned away from their O positions. Finallythe foils of the present invention are designed to be applied to anexisting calculating machine with no material modification of themachine construction and in a manner not to interfere in any way withthe operation of the associated machine.

Other objects and advantages will become apparent from a considerationof the following description and the appended claims in conjunction withthe accompanying drawings wherein:

Fig. l is a fragmentary, longitudinal cross-sectional view through therear portion of a conventional Friden calculating machine, showing checkdials and Zero foils for the check dials;

Fig. 2 is a fragmentary cross-sectional view on enlarged scalesubstantially on the section plane of Fig. l, as indicated by the lines2 2 on Fig. 4, showing the check dials and the zero foils therefor;

Fig. 3 is a fragmentary cross-sectional view on the horizontal planeindicated by the line 3-3 of Fig. 2;

Fig. 4 is a fragmentary cross-sectional View, on an enlarged scale, of afront view of the present invention, such as along the transversevertical planes indicated by the lines 4 4 of Fig. l;

Fig. 5 is a fragmentary plan view of the mechanism shown in Figs. l to4, such as taken along the horizontal plane indicated by the line 5 5 ofFig. 4; and

Fig. 6 is a perspective view of the foil elements shown particularly inFigs. 3, 4 and 5.

With continued reference to the drawings, the numeral i generallydesignates the frame of the calculating machine, which frame, inaddition to other components not illustrated, includes transverse framemembers 11, 12, 13, i4 and l5, disposed in spaced and parallelrelationship to each other and substantially perpendicular to the base,not illustrated, of the machine, and side plates, of which the left-handside plate is shown and designated at 16. A register, or accumulator,carriage, generally indicated at 20, is mounted for transverse sliding,or shifting, movements on the fixed frame, including the components 11to 16. The carriage comprises a tubular carriage frame 21 of generallyrectangular shape, the rear side of which is slidably mounted on a rail22 mounted on the inner side of the rear transverse frame member 15 nearthe upper edge of this frame member and the front end of which ismounted on rollers 25 and carried by an upper transverse member 26 ofthe fixed frame.

A transverse main, or power, shaft 30 extends across the machineimmediately in front of the frame crossmember 11 and is journalled onthis cross-member. A plurality of actuator shafts 33, usually 6 innumber, extend rearwardly from the shaft 30 in perpendicularrelationship to this shaft, with their axes substantially in a commonplane including the axis of the shaft 30. These actuator shafts arejournalled in the frame cross-members 11 and 13. The drive shaft 30 isdrivingly connected to the several actuator shafts 33 through individualmiter gear drive connections 34 and is itself driven from the machinemotor through a suitable cyclic clutch, as is fully disclosed in PatentNo. 2,229,889, granted January 28, 1941, to C. M. F. Friden.

Each actuator shaft 33 carries a pair of actuator drums, as indicated at35 and 36, and each of these drums carries two sets of consecutivelystepped gear teeth, as indicated at 40 and 41, for the drum 35. Theseries of teeth 40 is arranged to impart to a corresponding selectiongear from one to five angular increments of onetenth of a rotation. Theseries of teeth 41 are arranged to impart to a second gear co-axial withthe first gear from six to nine rotational increments of one-tenth of arotation each.

A keyboard, generally indicated at 42, is securely mounted on themachine to extend forwardly from the frame cross-member ii and includesa keyboard frame 43 and a plurality of keys having stems 44 slidablymounted for vertical movement in the keyboard frame 43. The keys arearranged in ordinal rows, there being ten rows of keys for a machinehaving six actuator shafts 33, with the keys in each row numbered from lto 9. This constitutes a full keyboard, as disclosed in the FridenPatent No. 2,229,889, referred to above. Selection slides are mountedfor longitudinal movement within the machine frame below the keyboard42. These slides are arranged in ordinal pairs, as indicated at 45 and46, with each pair disposed below a corresponding ordinal row ofkeyboard keys. The ordinal selection slides 45 and 46 are provided intheir upper edges with notches having dierentially inclined faces, asindicated at Si?. Each key stern carries near its lower end aperpendicularly projecting pin 51 which engages with the inclined face50 of the corresponding selection slide notch. The notches in the twoslides 45 and 46 of each pair of slides are so arranged that the slide45 is moved by depression of the "1 to 5 keys of the coordinal row ofkeyboard keys, and the se lection slide 46 is moved by depression of the6 to 9 keys of the same row. The inclined faces of the notches are sosloped that the slides will be moved a differential amount correspondingto the digit number of the key depressed. The slides are pivotallymounted on the upper ends of supporting links 52, which links arepivotally mounted at their lower ends on the machine frame. Each slideis provided with a rearward extension 53 which extends slidably througha notch 54 in the upper edge of the frame cross-member 1l and over thecorresponding actuator drum 35 or 36.

A plurality of square shafts 55 are disposed above, and parallel to, theactuator shafts 33, being journalled in frame cross-members 11, 12 and15. ln the Friden-type calculator having a ten-row keyboard, there willbe ten square shafts 55, which square shafts are disposed one at eachside of the five lowest order actuator shafts 33.

The sixth actuator shaft does not carry stepped actuating drums 35 and36 but is provided for the operation of the division mechanism of themachine, which constitutes no part of the present invention.

A pair of selection gears 56 and 57 are slidably mounted on each squareshaft S against rotation relative to the shaft. The coordinal selectionslide 45 is connected to the gear 56 by suitable means, such as the yoke60 on the rear end of the rear extension of this slide, engaging in anannular groove in the hub of the gear 56, while the slide 46 isconnected to the gear S7 by a similar yoke 61, on the rear end of therear extension 53 of this slide, engaging in an annular groove in thehub of the gear 57.

With this arrangement, the gear 56 is differentially set relative to theseries of actuator teeth 40 when any of the l to 5 keys of the coordinalrow of keyboard keys is depressed, to rotate the square shaft 55 thecorresponding number of angular increments. The gear 5'7 isdifferentially set relative to the series of actuator teeth 41 when anyof the 6 to "9 keys of the coordinal key row is depressed, to rotate thesquare shaft 55 through the corresponding number of angular incrementswhen the machine is cycled.

A plurality of accumulator dial assemblies, generally indicated at 65,are mounted in ordinal and parallel relationship in the carriage frame21. Each such assembly includes a dial shaft 66 suitably journalled inthe carriage frame 21 and extending perpendicularly to the square shafts55. Each such dial shaft carries a beveled dial assembly, or accumulatordrive gear 67 on its lower end, below the carriage frame 21, and anumbered dial 68 of truncated conical shape on its upper end, above thecarriage frame 21. ABetween the gear 67 and the bottom surface of thecarriage frame 21 each shaft 66 caries a tenstransfer cam 70 whichcooperates with a tens-transfer bellcrank lever 71 to make atens-transfer setup in a manner presently to be described. Within thetubular carriage frame 21, each shaft 66 carries a centralizing detentgear 72 and a mutilated resetting gear 73, the latter of which may beactuated by a resetting slide 74 to return the corresponding dialassembly from any differentially set position back to its 0 position inthe manner wellknown in the art.

Each square shaft 55 carries, below the dial assembly gear 67, anadd-subtract gear assembly 75 comprising a cylindrical intermediate, orspool portion, 76 slidably mounted on the corresponding square shaft 55against rotation relative to the square shaft, and beveled gears 77 and78 disposed, one at each end of the spool 76 and alternativelyengageable with a corresponding dial assembly gear 67, to impart to thedial shaft 66 the same number of rotational increments imparted to thecoordinal square shaft 55 by the associated actuator drum 35 or 36. Theadditive or subtractive position of gear assembly 75 is controlled by anadd-subtract gate, generally indicated at 80, which gate comprises astrap 81 disposed below the gear spools 76 and between the gears 77 and78 and mounted on spaced legs 82. The legs 82 are, in turn, mounted on atransversely extending shaft 83, movement of which is controlled by theadd-subtract keys of the machine and by a resilient centralizer device,in the manner well-known in the art. The add-subtract gate is effectiveto either hold the add-subtract spools in a centered position in whichneither gear 77 nor 78 engages the corresponding gear 67 (Fig. l); or inthe add position, in which the gear 77 meshes with the gear 67; or in asubtract position, in which the gear 78 meshes with the correspondinggear 67, this arrangement being fully disclosed -in the Friden Patent2,229,889, referred to above.

When a dial assembly 65 has been turned through angular intervals ineither direction from its 0 position, its tens-transfer cam 70 engagesthe rearward end of the associated tens-transfer lever 71 and rocks thislever about its pivotal connection 88. These levers 71 are so shapedthat the depending lug 87 on the transfer lever 71 will engage theforward flange 86 of the transfer gear assembly of the next higher orderand shift this gear assembly forwardly to its tens-transfer position.Detenting pins 90 extend between, and are supported at their ends in theframe cross-members 13 and 14, there being a detenting pin for eachtransfer gear assembly 85. Each detenting pin has thereon a pair ofspaced annular flanges 91 which. receive therebetween the rearwardflange 86 of the associated tens-transfer gear assembly 85. The pins 90are detented in either the tens-carry or inoperative position of theassociated tens-transfer gear assembly 85 to releasably hold thetens-transfer gears in either of these positions. Each of the actuatorshafts 33 carries a pair of tens-transfer teeth, as indicated at 92,spaced angularly and longitudinally of the associated shaft 33, one ofthese teeth being engageable with the tens-transfer gear at one side andthe other with the tens-transfer gear at the other side of thecorresponding actuator shaft. When a tens-transfer gear has been shiftedto its tenstransfer position, as explained above, and the machine iscycled, near the end of the cycle the appropriate tenstransfer tooth 92will engage a tooth of the shifted tenstransfer gear assembly 85 andimpart to such gear assembly a single rotational increment which willrotate the associated square shaft 55 and the corresponding dial shaft66 through one unit space to advance the corresponding dial 68 one unitspace in either the additive or subtractive direction. After thetens-transfer has been completed, as described above, a restore cam 93,mounted on the actuator shaft 33, engages the forward end of thecorresponding detenting pin 90 and restores this pin and thetens-transfer gear assembly 85 connected thereto to their rearward, orinoperative, position.

A revolutions counter, generally indicated at 95, is mounted in thecarriage forwardly of the accumulator register dial assemblies 65. Thecounter comprises a plurality of ordinally arranged dial shafts 96, eachof which iszdisposed perpendicular to a corresponding register dialshaft'66 with its rotational axis in a common horizontal planesubstantially perpendicular to the plane of the rotational axes of theregister dial shafts 66. A numbered dial 97 is mounted on each counterdial shaft 9.6. Each counter dial shaft carries a mutilated gear 98engaged by a longitudinally movable clearing rack 99 for clearing thecounter register. Each counter dial shaft 96 also carries a 'shaftrotating gear 100. The counter register mechanism includes an actuator102 of Well-known construction and vfully disclosed in the Friden PatentNo. 2,229,889 referred to above, which actuator is' effective to turnthe counter dial assemblies in a manner to register the number ofmachine cycles occuring during any particular operation of the machine.A-s this mechanism is all fully disclosed in the abovementioned FridenPatent No. 2,229,289 and constitutes no portion of the presentinvention, a more detailed description is considered unnecessary for thepurposes of the present disclosure.

The machine carriage is provided with a cover 105, which cover isprovided with apertures or window openings, as indicated at 104 and 107,through which the register dials 68 and the counter dials 97 may beviewed by the operator of the machine.

The check dial assembly of the machine, as shown in the Friden et al.Patent No. 2,279,456, is generally indicated at 106 and comprises ahousing 107 of rectangular cross-sectional shape, extending transverselyacross the fixed portion of the machine between the rear end of thekeyboard 42 and the front side of the carriage 20 and mounted on themachine frame cross-member 26 and the r-ear end of the keyboard frame43. This housing 107 is provided with an arched cover 108, detachablysecured to the housing in covering relationship, which housing isprovided with apertures or window openings 109 through which the checkdials may be viewed by the machine operator.

A check dial shaft. 110 extends longitudinally through the housing andis mounted at its ends in supports carried by the housing 107. Aplurality of ordinally arranged check dial assemblies, generallyindicated at 115, are mounted on the shaft 110. Each of the check dialassemblies, as particularly illustrated in Figs. 3 and 5, comprises apair of stepped hubs 116 and 117 coaxially journalled on the shaft 110in end-to-end relationship to each other, each of which hubs is providedwith a nine-tooth gear, as indicated at 118 and 119. A dial 12d, havinga centrally apertured webbed portion 121, is coaxially mounted on thehub 116 at the side of the gear 118 nearest to gear 119. This dial isprovided with an annular ilange portion 122 extending from theperipheral edge of the web portion 121 in a direction away from the gear118 and carrying numerals from 0 to 5, angularly spaced-apart around aportion thereof.

A washer 123 is mounted on the hub 116 between the dial web 121 and anannular flange, or rib, 125 on the inner end of the hub. This Washer isdrivingly secured to the hub and has a laterally projecting tongue 126(Fig. 3) received in an aperture in the dial web. A reinforcing washer,or cam, 124 is disposed between the dial flange and the gear 118 so thatthe dial web is sandwiched between the washers 124 and 123. It iscontemplated that the gears 118 and 119 will be formed separately fromthe hubs and that during the assembly of each unit, the dial and washerswill be assembled on the hub against the hub flange 125 and that thecorresponding gear will then be pressed onto the hub.

The hub 11'7 carries a dial 128 secured on the hub between the gear 119and the inner end of the hub by suitable washers and a flange, asdescribed above in connection with the dial 120. The dial 128 has anannular ange portion 129 which extends from the dial web in a directionaway from the gear 119 and surrounds the flange 122 of the dial 120 sothat the dials 121B and 12S are nested together. The dial flange 129carries numerals from "6 to 9, inclusive, and isalso provided with awindow, or opening, 130 through which the numerals on the dial flange122 are selectively visible when the dial 12S is in its normal,inactive, position.

A second shaft 135 extends longitudinally of the housing 167 below, andparallel to, the shaft 110 and is mounted at its ends in suitablesupports carried by the housing. A plurality of sector assemblies,generally indicated in 136, are rockably mounted on the shaft 135 inspaced relationship, there being one such sector assembly for each dialhub gear 118 or 119. It is understood that, for a ten-bank machine,there will be ten check dial assemblies and that each assembly will havetwo hub gears. Thus, there will be twenty sector assemblies 136 and eachsector assembly will be connected to a corresponding one of the twentyselection slides 45 and 46,. in a manner to be presently described.

Each sector assembly 136 comprises an arcuate rack segment 137 having ahub journalled on the shaft 135 and a series of rack teeth 138 meshingwith the teeth of the corresponding dial hub gear 118 or 119, and anactuating lever 146, also having a hub journalled on the shaft 135. Theactuating lever has a bifurcated arm 141 projecting radially from thehub and having a notch, or opening, receiving a pin 142 projectinglaterally from the rearward extension 53 of t-he corresponding slide 45or 46.

Each actuating lever also has an arm 143 projecting radially from thehub portion of the lever substantially opposite the arm 141 and disposedbetween a set screw td and a spring 145, both carried by thecorresponding sector 137 so that the sector can be angularly adjustedrelative to its actuating lever to accurately center the numbers on thedial flanges 122 and 129 in the corresponding window opening 109 of thecover 108.

With the above-described arrangement, when a numeralV or digit key ofthe keyboard is depressed and differentially moves the correspondingselection slide 45 or 46 in a direction forwardly of the machine, or tothe left as is viewed in Fig. 1, the corresponding sector assembly 136is rocked a predetermined angular amount about its supporting shaft 135and rotates the corresponding check dial gear 118 or 119 a correspondingangular amount, thereby bringing the proper numeral on the dial flange129 into registry with the corresponding window opening 109, or theproper numeral on the dial flange 122 into registry with the windowopening 130 in the associated dial flange 129 and the cover windowopening 109. The check dial mechanism so far described is fullydisclosed in the Friden et al. Patent No. 2,279,456 referred to aboveand provides a means whereby a calculating machine operator can easilyread the number which has been entered into the keyboard of the machineto check the accuracy of the entry value before the machine is actuatedto use this value in a machine operation, such as an addition,subtraction, multiplication or division operation.

The arrangement, as described above and disclosed in the Patent No.2,279,456, has been found to operate entirely satisfactorily but has thedefect that all of the zeros in the check dial arrangement are visibleat all times to the machine operator and this renders somewhat diicultthe accurate reading of the entry value shown in the check dials andalso the accurate determination of the ordinal position of the entryvalue, particularly where the entry value contains a relatively smallnumber of digits. The present invention provides means for covering thecheck dial window openings rand control means for uncovering thoseopenings to the right of a selected order of the keyboard; or, in theabsence of any such selection, to the right of the highest order digitin an entry value, while leaving the window openings to the left of suchselected order or highest order digit closed, so that the zeros to theleft of the highest order digit or the selected keyboard order do notshow. This mechanism has been hereinbefore referred to as a zero foil,or cover, mechanism and comprises a plurality of ordinally arrangedwindow covering levers 146; there being one such lever for each checkdial assembly 115.

The levers 146 are rockably mounted on a third shaft 147 which extendslongitudinally of the housing 1117 below the shaft and rearwardly of theshaft 135 and is mounted at its ends on the check dial housing. As isparticularly shown in Figs. 2, 4 and 5, each of the levers 146 is yadouble lever having two legs 149 and 151) disposed in spaced andparallel relationship to each other to provide a U-shaped structurewhich is rockably mounted ,at its open end on the shaft 147. The otherend of the U-shaped member is closed by an integral intermediate, orbight, portion 152, which, when the lever is in its operative, or zeroblanking, position shown in Fig. 1, covers the corresponding check dialwindow opening 139 in the cover 1133. The legs 149 and 150 of each coverlever 146 are disposed .at respectively opposite sides of thecorresponding check dial assembly, including the dials and 12S, and arelongitudinally curved to extend forwardly and then upwardly around theforward portions of the check dial hubs. The levers are resilientlyurged to their window closing position, as shown in Fig. l, byindividual springs 159 connected between the levers anda springconnecting bar 151 secured between the cover 1118 and the rear upperedge of the housing 1117. rhe spacing washers 124 and 154 of each checkdial assembly serve also as cams 124 and 154, each of which has acircular lobe portion extending through the major portion of itscircumference, and a low portion 155 of limited angular extent. Each ofthe lever legs 149 and 15@ has, intermediate its length, an upwardlyextending projection 15o, the outer end of which engages the peripheryof the corresponding cam 124 `or 154. The low portions are so locatedthat when a dial is in its 0 position, the lever projections 156 are inthe corresponding low portions 155 and the intermediate, or bight,portion 152, of the lever is in position to cover the correspondingwindow opening 109. When either of the corresponding dials 12) or 128 isturned away from its fullcycle or O position, the notch, or low portion,155 of the respective cam rotates away from the corresponding projection156, so that the projection will be engaged by the circular lobe portion154 of the cam, and this will force the lever down and hold it down in aposition in which the corresponding window opening 109 is uncovered.

As is particularly shown in Fig. 5, each cover lever 146 is providednear its upper or free end with laterally directed extensions 157 and158 extending outwardly and slightly forwardly from the vcorrespondinglever legs 149 and 150, respectively. The extension 157 is reverselybent to include a portion 170 extending perpendicularly to the left fromthe corresponding lever leg 149 and a portion 171 extending forwardly,substantially perpendicular to the latter portion; while the extension158 is substantially L-shaped and includes a portion 172 extending tothe right from the lever leg 150 from which it projects. It will benoted in Fig. that the right-hand projection 172 of each extension 158overlies the forwardly extending portion 171 of the projectionimmediately to the right thereof, which projection is lassociated withthe check dial assembly of the next lower order. Thus, whenever a leverof a check dial assembly above the lowest order is forced downwardly bythe turning of the associated check dial to show a digit value, theprojection 172 of this lever will engage the projection 171 of the leverto its right and force this lever down to uncover the correspondingcheck dial window opening, and the second lever will engage and forcedown the lever to the right of it, etc. Thereby the window opening inregistry with a check dial carrying the highest significant digit of anentry value, and all of the window openings to the right thereof, willbe simultaneously uncovered.

While the above-described arrangement will provide a construction inwhich all of the window openings to the right of the highest significantdigit of an entry value will be uncovered yand all of those to the leftof the order carrying such highest significant digit will remain closed,it is, at times, desirable to show a predetermined number of zeros tothe left of the highest significant digit in a particular entry value.This is accomplished in the present arrangement by the provision of adecimal setting pointer, as generally indicated at 169.

The decimal pointer assembly 16@ comprises a bar 161 extending acrossthe outer surface of the cover 108 immediately in front of the windowopenings 1:99 and having its ends secured to the cover and itsintermediate portion spaced above the cover, and a manually settableslide 162 mounted on, and slidable along, the bar 161.

The slide 162 has, on the portion thereof adjacent to bar 161, a pointerformation 164, by means of which the operator can accurately determinethe setting of the slide relative to the orders of the check dials, andhas a portion 165 extending downwardly from the bar 161 through a slot166 in the cover MS and provided at its lower end with anarrowhead-shaped formation 167. The formation 167 has opposite edgesinclined upwardly and to the left and upwardly and to the right so thatwhen the slide is moved to the left or right along the bar 161 theseinclined edges of the slide formation 167 will override the forwardextensions 171 of the zero foil levers 146 and force the upper, or free,ends of these levers downwardly to uncover the corresponding windowopenings 109 in the check dial cover. The bottom end of the formation167 is flattened, as indicated at 168, so that the lever 171, at theordinal location at which the slide 162 is stopped, will be held downand all of the zero foil levers to the right of this lever will also beheld down because of the overlapping arrangement of the lever extensions172 and 171, as described above. Thus, all of the check dial windowopenings to the right of the position of the zero pointer slide 162 willbe held down in position to uncover the corresponding check dial windows109, and the windows to the left of the position of the slide willremain covered, unless a check dial of an order to the left of that atwhich the slide is set is turned away from its zero position. In thelatter case its zero foil lever will be moved down by the correspondingcam 124 or 154 and any levers between this rotated check dial and theordinal position of the slide 162 will also be forced downwardly totheir window opening position.

With this arrangement, the calculating machine operator can not onlydetermine the accuracy of an entry value, but can also readily determinethe ordinal position of the value entered, and whether or not the valuecontains the proper number of digits properly related to the selecteddecimal order at which the machine is being operated.

The invention may be embodied in other specific forms without departingfrom the spirit or essential characteristics thereof. The presentVembodiment is, therefore, to be considered in all respects asillustrative and not restrictive, the scope of the invention beingindicated by the appended claims rather than by the foregoingdescription, all changes which come within the meaning and range ofequivalency of the claims are, therefore, intended to be embracedtherein.

What is claimed is:

1. In ay calculating machine having differentially settable selectionmechanism including a pair of selection slides in each order settable todifferent digit positions of the same series of digits, value displayingmeans including a pair of nested dials in each order mounted forindependent rotational movements, means connecting each of said dials toa corresponding selection slide of the same order to move said dials todifferent angular positions indicating the digit positions of the`corresponding selection slides, each of said dials having a series ofnumbers thereon and theouter' of said dials having at one end of theseries of numbers thereon an opening through which the numbers on theassociated inner dial can `be viewed, and a cover covering said dialsand having window openings therein through which the numbers on saiddials can be viewed, shield means comprising members mounted oneadjacent each pair of nested dials for movement into and out of closingrelationship to the corresponding window openings in said cover, meansresiliently biasing said members to window closing position, meansacting between said dials and said members moving said members to windowopening position when the corresponding dials are turned away from theirO position, an ordinally positionable member operative to move thecoordinal shield member from a window closing to a window openingposition, and lateral projections on said shield members arranged inoverlapping relationship from left to right whereby the movement of anyshield member to window opening position moves all shield members to theright thereof to such window opening position.

2. In a calculating machine having differentially settable selectionmechanism including a pair of selection slides in each order settable todifferent digit positions of the same series of digits, value displayingmeans including a pair of dials in each order mounted for independentrotational movements, means connectinn each or Said dials to acorresponding selection slide of the same order to move said dials todifferent angular positions indicating the digit positions of thecorresponding selection slides, and a cover overlying said dials andhaving window openings therein through which said dials can be viewed,shield means for said dials comprising a member rockably mountedadjacent each pair of dials for movement into and out of coveringposition relative to the corresponding window openings in said cover,means biasing said members to window covering position, means actingbetween said dials and said members to move any member to window openingposition when either dial of the coordinal pair of dials is turned fromits O position, a manually positionable means operative to rock a selected shield member 'from a window Closing to a window openingposition, and projections extending from said members and overlappingeach other in a relationship such that when a member is moved to itswindow opening position, all of the members to the right of such memberwill be simultaneously moved to window opening position.

3. In a calculating machine having differentially settable selectionmechanism including at least one selection member in each order settableto different digit positions of the same series of digits, valuedisplaying means including at least one dial rotatably mounted in eachorder, means connecting each dial to a corresponding selection member ofthe same order to move said dials to angular positions indicating thedigit positions of the corresponding selection members, and a coveroverlying said dials and provided with window openings through whichsaid dials can be viewed, shield means for said dials comprising membersrockably mounted one in each order and adjacent the corresponding dialsfor movement into `and out of position to close the corresponding windowopenings in said cover, means biasing said members to window closingposition, means acting between said dials and said roclcable members formoving any member to window opening position when a coordinal dial isturned from its position, overlapping means on said rockable memberseffective when one member is moved to window opening position tosimultaneously move all the rockable members to the right of said onemember to window opening position, and a decimal marker slidable alongsaid cover from order to order of said value displaying means andengaging said overlapping means to move the rockable member at theordinal position of said decimal marker and all rockable members to theright thereof to window opening position.

4. In a calculating machine having selection mechanism includingordinally arranged pairs of endwise movable slides differentiallysettable to represent different value ranges of the same series ofvalues, value indicating means including ordinally arranged pairs ofoverlapping indicator elements mounted for independent movement andconnected to corresponding slides in the same orders for movementthereby, a cover overlying said indicator elements and having windowopenings therein, and window closing members movably mounted adjacentsaid indicator elements and moved to window opening position when thecoordinal indicator elements are moved away from their 0 positions,ordinally settable means effective to move the coordinal window closingmember away from its window closing position, and means operated by saidwindow closing members for moving all of the window closing members tothe right thereof away from their window closing position.

5. A check dial assembly for a calculating machine comprising anelongated housing, a first shaft extending longitudinally of saidhousing, check dials rotatably 10 mounted in ordinal arrangement on saidfirst shaft, a cover for said housing having ordinally arranged windowopenings through which said check dials can be viewed, a second shaftextending longitudinally of said housing, means mounted on said secondshaft and engaging said check dials to turn the latter to valueindicating positions, a third shaft extending longitudinally of saidhousing, levers mounted in ordinal arrangement on said third shaft andhaving thereon formations adapted to cover the coordinal window openingsin said cover, means urging said levers to position to cover said windowopenings, cams driven with said dials and engaging said levers toindividually move said levers to position to uncover said windowopenings when the coordinal dials are turned away from their 0positions, and an ordinally positionable member operative to move thecoordinal lever to a position to uncover the coordinal window opening,said levers having projections thereon so arranged that one projectionon all except the extreme right-hand lever overlies a projection on thelever immediately to the right thereof so that, when one lever is movedto window uncovering position, all levers to the right of said one leverwill be similarly moved.

6. A check dial assembly for a calculating machine comprising anelongated housing, a irst shaft extending longitudinally of saidhousing, check dials rotatably mounted in ordinal arrangement on saidrst shaft, a cover for said housing having ordinally arranged windowopenings through which said check dials can be viewed, a second shaftextending longitudinally of said housing, means mounted on said secondshaft and engaging said check dials to turn the latter to valueindicating positions, a third shaft extending longitudinally of saidhousing, levers mounted in ordinal arrangement on said third shaft andhaving thereon formations adapted to cover the coordinal Window openingsin said cover, means urging said levers to position to cover said windowopenings, and cams driven with said dials and engaging said levers toindividually move said levers to position to uncover said windowopenings when the coordinal dials are turned away from their 0positions, said levers having projection thereon so arranged that oneprojection 0n all except the extreme right-hand lever overlies aprojection on the lever immediately to the right thereof so that, whenone lever is moved to window uncovering position, all levers to theright of said one lever will be similarly moved, and a decimal pointerslidably mounted on said cover for movement from order to order alongsaid window openings and engaging the projections on said levers to movethe lever at and those to the right of the ordinal position of saiddecimal pointer to window uncovering position.

References Cited in the iile of this patentk UNITED STATES PATENTS1,142,079 Cleal June 8, 1915 2,104,051 Niemann Jan. 4, 1938 2,279,456Friden et al. Apr. 14, 1942

